The README, this license and all other non-BootROM files are licensed as CC0. All BootROMs use the license below.
(I made this up, but feel free to use it in your project)
This content is for archival purposed only. These devices extremely old and long since discontinued, so hopefully Apple doesn't care about them anymore.
Apple, if you want this repo taken down, just open an issue using the official Apple GitHub account, or any other way of verifying your authenticity, and I will take them down without a DMCA.